Some 50 firefighters were deployed to tackle the large fire in the single-storey sports complex building, which was so fierce that traffic was diverted off the nearby A1 due to drifting smoke plumes.

Nine fire crews were on the scene last night (Image: Nottinghamshire Fire and Rescue)

The roads around the site were also closed while fire crews worked, and eyewitnesses reported hearing explosions from within the building.

The efforts were scaled down at 2.30am, with three crews from Southwell, Stockhill and Carlton stations still on scene on Saturday morning alongside an incident commander (7.15am).

The nearby Newark Academy site was not affected by the fire, with a school spokesman saying: "Hugely grateful for the amazing professionals at Nottinghamshire Fire Service for keeping our school community safe."